真核生物和原核生物mRNA 5′至3′方向的降解机制.pdfVIP

Hereditas (Beijing) 2015 年 3 月, 37(3): 250 ―258 综 述 真核生物和原核生物mRNA 5′至3′方向的降解机制 1,2 1,2 1,2 1,2 1,2 许禔森 ，李学贵 ，焦德杰 ，谢兆辉 ，戴忠民 1. 德州学院生命科学学院，德州 253023 ； 2. 山东省高校生物技术与生物资源利用重点实验室，德州 253023 摘要 : RNA 降解是基因表达调节的重要途径，影响很多生命活动。近来，mRNA 降解机制有了很多新发现， 如真核生物中发现了一种mRNA 末端尿苷化介导的脱帽机制，和一条不依赖exosome 的3′→5 ′的mRNA 降解 途径。虽然真核生物与原核生物mRNA 降解途径非常相似，通常都有3 种：内切降解、5′→3 ′外切降解和3′→5′ 外切降解等，但两者mRNA 降解途径之间也存在很多差异，如5′→3 ′方向的外切降解是真核生物mRNA 最重 要的降解途径之一，但其在细菌中作用非常弱，且只在革兰氏阳性菌中发现。mRNA 降解的研究不仅深化了人 们对这一过程的认识，而且有助于新型药物的研发，以防御寄生虫、病毒或治疗人类疾病(如癌症)等。文章主 要综述了真核生物和原核生物mRNA 5 ′→3 ′方向的降解机制，并对其应用前景进行了展望。 关键词 : 5′→3 ′ mRNA 降解；基因表达；真核生物mRNA ；原核生物mRNA ；药物 Mechanism of 5′-to-3′ degradation of eukaryotic and prokaryotic mRNA Tisen Xu1,2, Xuegui Li1,2, Dejie Jiao1,2, Zhaohui Xie1,2, Zhongmin Dai1,2 1. Department of Biology, Dezhou University, Dezhou 253023, China; 2. Key University Laboratory of Biotechnology and Utilization of Bio-Resource of Shandong, Dezhou 253023, China Abstract: RNA degradation plays an important role in modulating gene expression and it affects multiple biolog- ical processes. There are three common degradation mechanisms of eukaryotic and prokaryotic mRNA: endonucleo- lytic, 5 ′-to-3 ′ and 3 ′-to-5 ′ exonucleolytic degradation. Differences do exist between the two kingdoms. For example, although the 5 ′-to-3 ′ exoribonucleolytic degradation is the primary degradation mechanism of eukaryotic mRNA, it plays a minimal role in bacteria, and only in Gram-positive bacteria. Recently, novel RNA degradation mechanisms have been revealed, such as a new eukaryotic mRNA decapping mode mediated by 3 ′-uridylation and a new 3 ′-to-5 ′ degradation pathway independent of exosome. These accumulating discoveries not only deepen the insight of mRNA degradation mechanism